Surgical fastener applying apparatus

ABSTRACT

A surgical fastener applying apparatus for applying fasteners to body tissue. The apparatus includes a clamping lever including a cantilevered locking member for engaging a catch member positioned at the proximal portion of a cartridge receiving half-section of the apparatus to retain the clamping lever in a clamped position. The clamping lever can include a protrusion which is receivable in a depression on the cartridge receiving half-section. The apparatus includes a disposable firing assembly and cartridge.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/472,546, filed May 16, 2012, which claims benefit of and priority toU.S. Provisional Application No. 61/494,967, filed Jun. 9, 2011, theentire contents of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical fastener applying apparatusand, more particularly, to a surgical fastener applying apparatus havingreusable and disposable components.

2. Discussion of Related Art

Surgical fastener applying apparatus, wherein tissue is first grasped orclamped between opposing jaw structures and then joined by means ofsurgical fasteners, are well known in the art. In some such apparatus, aknife is provided to cut the tissue which has been joined by thefasteners. The fasteners are typically in the form of surgical staples,although, other surgical fasteners may also be utilized, such as, forexample, clips or two part polymeric surgical fasteners.

Surgical fastener applying apparatus typically include two elongatedbeam members which are used to capture or clamp tissue therebetween.Typically, one of the beam members carries a disposable cartridgeassembly which houses a plurality of staples arranged in at least twolateral rows, while the other beam member includes an anvil whichdefines a surface for forming the staple legs as the staples are drivenfrom the cartridge assembly. Where two part fasteners are used, the beammember which includes the anvil carries a mating part of the two partfastener, e.g. the receiver. Generally, the staple formation process isaffected by the interaction between one or more longitudinally movingcamming members and a series of individual staple pushers. As thecamming members travel longitudinally through the cartridge carryingbeam member, the individual pusher members are biased upwardly into abackspan of the staples supported within the cartridge assembly tosequentially eject the staples from the cartridge. A knife may beprovided to travel with the camming members between the staple rows tocut the tissue between the rows of formed staples. An example of such aninstrument is disclosed in U.S. Pat. No. 7,631,794, which isincorporated herein in its entirety by reference.

Because of the dangers associated with improper sterilization, surgicalfastener applying apparatus are typically disposable after use. Althoughthe cartridge assembly may be replaced to perform multiple fastenerapplying operations on a single patient, the fastener applying apparatusis typically disposable after a surgical procedure has been completed.This requirement of disposability may increase the costs associated withsurgical procedures. Although reusable fastener applying apparatus havebeen developed, such apparatus can be overly complex and prove difficultto sterilize.

A need exists in the art for a fastener applying apparatus whichincludes reusable components, is not overly complex and is configured tofacilitate proper sterilization after use in a surgical procedure.

SUMMARY

The present disclosure relates to a surgical fastener applying apparatusfor applying surgical fasteners to body tissue. According to one aspect,the apparatus includes an anvil half-section including a distal anvilportion and a proximal handle portion and a cartridge receivinghalf-section defining an elongated channel member having a distalportion dimensioned to releasably receive a cartridge and a proximalportion configured to support a firing assembly. The elongated channelmember includes a catch member positioned at the proximal portion. Aclamping lever is secured to the cartridge receiving half-section. Theclamping lever has a proximal portion and a distal portion and includesa handle portion and a cantilevered locking member which is connected tothe proximal portion of the clamping lever by a living hinge. Thecantilevered locking member includes an engagement member. The clampinglever is operably associated with the anvil half-section and thecartridge receiving half-section and is movable from an unclampedposition to a clamped position to releasably secure the anvil portion ofthe anvil half-section in close approximation with the cartridge. In theclamped position, the engagement member of the cantilevered lockingmember releasably engages the catch member to releasably retain theclamping lever in the clamped position.

In one embodiment, the cantilevered locking member includes a fingerengagement surface which is depressible to effect disengagement of theengagement member and the catch member. The proximal end of the clampinglever may define a cutout in which the cantilevered locking member issupported. The cantilevered locking member may in some embodimentsdefine an opening, the engagement member being positioned within theopening.

A spring member can be provided which is supported on the clamping leverand is positioned to engage the cartridge receiving half-section to urgethe clamping lever to the unclamped position.

In one embodiment, a firing assembly is provided which is configured tobe releasably secured within the proximal portion of the cartridgereceiving half-section. The firing assembly can include a firing leverand a cam bar fixedly secured to the firing lever. The firing assemblycan further include a stationary housing which is configured to bereleasably supported in the proximal portion of the cartridge receivingportion. The firing assembly may also include a knife actuating barwhich is configured to engage a knife supported within the cartridge.

In one embodiment, the firing assembly further includes a stationaryhousing including a U-shaped frame, a guide block axially fixed withinthe U-shaped frame and a slide block slidably positioned with theU-shaped frame. The firing assembly can also include a firing lever thatis pivotally secured to the slide block and a cam bar that is fixedlysecured to the slide block such that the slide block is slidable throughthe U-shaped frame to advance the cam bar through the distal portion ofthe elongated channel member. The U-shaped frame can include a bottomwall and a pair of sidewalls, wherein each of the sidewalls has aproximal end defining a cantilevered section having a protrusion whichis positioned to be releasably received in a recess formed in theproximal end of the elongated channel member to releasably retain thestationary housing within the proximal portion of the elongated channelmember.

In one embodiment, the cartridge receiving half-section includes asidewall defining a depression and the clamping lever includes asidewall defining a protrusion, the protrusion is positionable withinthe depression to prevent the clamping lever from moving to a positionwhere it could be disengaged from the cartridge receiving section. Inone embodiment, the clamping lever is releasably secured to thecartridge receiving half-section.

In one embodiment, the firing assembly includes a stationary housinghaving a sidewall with a slotted proximal end to define a cantileveredsection with a protrusion, and the cantilevered section is flexibleinwardly to releasably secure the firing assembly.

In another aspect, a surgical fastener applying apparatus is providedhaving an anvil half-section including a distal anvil portion and aproximal handle portion and a cartridge receiving half-section definingan elongated channel member. The elongated channel member has a distalportion dimensioned to releasably receive a cartridge and a proximalportion configured to support a firing assembly. The cartridge receivinghalf-section further includes a sidewall defining a depression. Aclamping lever is secured to the cartridge receiving half-section andhas a proximal portion and a distal portion and a handle portion. Theclamping lever is operably associated with the anvil half-section andthe cartridge receiving half-section and is movable from an unclampedposition to a clamped position to releasably secure the anvil portion ofthe anvil half-section in close approximation with the cartridge. Theclamping lever further includes a sidewall having a protrusion, theprotrusion being positionable within the depression of the cartridgereceiving half-section to prevent the clamping lever from moving to aposition where it could be disengaged from the cartridge receivingsection.

In one embodiment, the clamping lever is mountable to the cartridgereceiving half-section at a first angle and rotated toward a clampingposition to move the protrusion within the depression. The clampinglever in one embodiment has a C-shaped recess and the cartridgereceiving section has a pivot member having a flat. The C-shaped recesscan have a width smaller than a diameter of the pivot member such thatthe pivot member needs to be slid into the recess along a surface of theflat.

In one embodiment, the clamping lever is inserted into engagement withthe pivot member at an obtuse angle to the proximal portion of thecartridge receiving half-section and is pivoted to an acute angle to theproximal portion of the cartridge receiving section.

In one embodiment, the clamping lever has a flange having a cutoutdimensioned to receive a lateral support of the anvil half-section.

The apparatus can further include a spring member which is supported onthe clamping lever and positioned to engage the cartridge receivinghalf-section to urge the clamping lever to the unclamped position.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed surgical fastenerapplying apparatus will now be described herein with reference to theaccompanying figures wherein:

FIG. 1 is a side perspective view of one embodiment of the presentlydisclosed surgical fastener applying apparatus in the clamped position;

FIG. 2 is a side perspective view of the surgical fastener applyingapparatus shown in FIG. 1 in the open position;

FIG. 2A is a side view of a portion of the cartridge receivinghalf-section and the clamping lever during assembly of the clampinglever and the cartridge receiving half-section;

FIG. 2B is a side perspective view of the fastener applying apparatusshown in FIG. 1 in the closed, unclamped position;

FIG. 3 is a side perspective view of the surgical fastener applyingapparatus shown in FIG. 1 with parts separated;

FIG. 3A is a bottom, side cross-sectional view of the clamping lever ofthe surgical fastener applying apparatus shown in FIG. 1;

FIG. 4 is a side perspective view of the cartridge receivinghalf-section of the surgical fastener applying apparatus with the singleuse loading unit (“SULU”) and the firing assembly supported within thecartridge receiving half-section;

FIG. 5 is an enlarged view of the indicated area of detail shown in FIG.4;

FIG. 6 is a perspective view from above of the cartridge receivinghalf-section of the surgical fastener applying apparatus with the SULUand the firing assembly supported therein;

FIG. 7 is an enlarged view of the indicated area of detail shown in FIG.6;

FIG. 8 is a front end perspective view from above of the firing assemblyof the surgical fastener applying apparatus shown in FIG. 3;

FIG. 9 is an enlarged view of the indicated area of detail shown in FIG.8;

FIG. 9A is a side perspective view of the channel member with the firingassembly releasably supported therein;

FIG. 9B is an enlarged view of the indicated area of detail shown inFIG. 9A;

FIG. 9C is a side perspective view of a central portion of the channelmember;

FIG. 10 is a rear end perspective view from above of the firing assemblyshown in FIG. 8;

FIG. 11 is an enlarged view of the indicated area of detail shown inFIG. 10;

FIG. 12 is a side perspective view of the firing assembly shown in FIG.10 with parts separated;

FIG. 12A is a bottom, side perspective view of the cam bar of the firingassembly shown in FIG. 12;

FIG. 12B is a bottom, side perspective view of the firing lever of thefiring assembly shown in FIG. 12;

FIG. 13 is a side perspective view of the SULU of the surgical fastenerapplying apparatus shown in FIG. 1;

FIG. 14 is an enlarged view of the indicated area of detail shown inFIG. 13;

FIG. 15 is a front perspective view of the SULU shown in FIG. 13;

FIG. 16 is an enlarged view of the indicated area of detail shown inFIG. 15;

FIG. 17 is a side perspective view with parts separated of the SULUshown in FIG. 15;

FIG. 18 is a side cross-sectional view of the surgical fastener applyingapparatus shown in FIG. 1 in the open position;

FIG. 19 is an enlarged view of the indicated area of detail shown inFIG. 18;

FIG. 20 is an enlarged view of the indicated area of detail shown inFIG. 18;

FIG. 21 is a perspective view of the proximal end of the surgicalfastener applying apparatus shown in FIG. 18 in the open position;

FIG. 22 is an enlarged view of the indicated area of detail shown inFIG. 18;

FIG. 23 is a perspective view of the proximal end of the clamping leverof the surgical fastener applying apparatus shown in FIG. 1;

FIG. 24 is a side perspective view of the surgical fastener applyingapparatus shown in FIG. 1 in the clamped position;

FIG. 25 is a side cross-sectional view of the surgical fastener applyingapparatus shown in FIG. 24 in the clamped position;

FIG. 26 is an enlarged view of the indicated area of detail shown inFIG. 25;

FIG. 27 is an enlarged view of the indicated area of detail shown inFIG. 25;

FIG. 28 is a cross-sectional view taken along section lines 28-28 ofFIG. 26;

FIG. 29 is a top view of the surgical fastener applying apparatus shownin FIG. 1 as the firing assembly is moved through an actuating stroke toeject fasteners from the apparatus;

FIG. 30 is a side cross-sectional view of the surgical fastener applyingapparatus shown in FIG. 29 with the firing assembly in the actuatedposition;

FIG. 31 is an enlarged view of the indicated area of detail shown inFIG. 30;

FIG. 32 is an enlarged view of the indicated area of detail shown inFIG. 30;

FIG. 33 is a side cross-sectional view of the surgical fastener applyingapparatus shown in FIG. 1 after the apparatus has been fired and movedto the open position; and

FIG. 34 is an enlarged view of the indicated area of detail shown inFIG. 33.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed surgical fastener applyingapparatus in accordance with the present disclosure will now bedescribed in detail with reference to the drawings wherein likereference numerals identify similar or identical structural elements. Asused herein, as is traditional, the term “proximal” refers to the end ofthe apparatus which is closer to the user and the term distal refers tothe end of the apparatus which is further away from the user.

FIGS. 1-34 illustrate an illustrative embodiment of the presentlydisclosed surgical fastener applying apparatus designated generally assurgical stapler 10. Referring specifically to FIGS. 1-3, surgicalstapler 10 includes an anvil half-section 12, a cartridge receiving(supporting) half-section 14, a clamping lever 16, a cartridge or singleuse loading unit 18 (hereinafter “SULU”) and a firing assembly 20. Inone embodiment, anvil half-section 12, cartridge receiving half-section14 and clamping lever 16 are constructed to be reusable components and,as such, are constructed from a biocompatible material suitable forsterilization and repeated use, e.g., stainless steel. In contrast, SULU18 and firing assembly 20 are constructed to be disposable and, as such,may be constructed from any suitable biocompatible material, e.g.,plastics, metals, combinations thereof, having the requisite strengthcharacteristics. SULU 18 and firing assembly 20 can alternatively beconstructed as an integral unit to be loaded as a single unit into thecartridge receiving half-section 18.

Referring to FIGS. 3-7, cartridge receiving half-section 14 defines anelongated channel member 22 which defines a substantially U-shapedchannel 24 having a distal portion 24 a dimensioned to releasablyreceive a SULU (cartridge) 18 and a proximal portion 24 b dimensioned toreleasably receive firing assembly 20. Firing assembly 20 includes astationary housing 26 (see also FIG. 12) having a proximal end includingprotrusions 28 which extend into recesses 30 formed in a proximalportion of cartridge receiving half-section 14 to releasably secure theproximal end of firing assembly 20 within the proximal portion 24 b ofchannel member 22. The distal end of firing assembly 20 defines atriangular cutout 64 d which is positioned to receive a protrusion 65formed on an inner wall of channel member 22 (see FIGS. 9A-9C) toreleasably secure the distal end of firing assembly 20 within channelmember 22. The structure of firing assembly 20 will be discussed infurther detail below. Likewise, SULU 18 includes a pair of distalprotrusions 32 which are positioned in cutouts 34 formed at the distalend of channel member 22 to releasably secure SULU 18 within the distalportion 24 a of channel member 22. During assembly, firing assembly 20must be inserted into proximal portion 24 b of channel member 22 beforeSULU 18 is inserted into distal portion 24 a of channel member 22 aswill be discussed below. To position SULU 18 in channel member 22,protrusions 32 on SULU 18 are positioned within cutouts 34 while SULU 18is positioned above and at an angle to channel member 22. Thereafter,SULU 18 can be rotated downwardly into distal portion 24 a of U-shapedchannel 24. This allows for the drive components of firing assembly 20to properly align with components of SULU 18 and also facilitatesengagement of the firing assembly 20 with a knife 40 (FIG. 17) supportedwithin SULU 18. A proximal end of SULU 18 includes an outwardlyextending serrated surface 42 (FIG. 7) to facilitate gripping of theproximal end of SULU 18 to allow for removal and/or replacement of SULU18 from channel member 22. Prior to movement of stapler 10 to theclamped position, as will be discussed below, serrated gripping surface42 will not fully seat within distal portion 24 a of channel member 22.

Referring to FIGS. 8-12, firing assembly 20 includes stationary housing26, a knife actuating bar 44, a cam bar 46, a guide block 48, a firinglever 50, a slide block 52 and a pedal 54 (FIG. 12). In one embodiment,stationary housing 26 includes a U-shaped frame 60 including a bottomwall 62 and a pair of sidewalls 64. Each sidewall 64 is slotted at itsproximal end to define a cantilevered section 64 a (FIG. 11) whichsupports a respective protrusion 28. Cantilevered sections 64 a allowprotrusions 28 to flex inwardly into recesses 30 of channel member 22(FIG. 21) to releasably secure firing assembly 20 within proximalportion 24 b (FIG. 3) of channel member 22 as discussed above. Thedistal end of each sidewall 64 defines a proximal step 64 b, a distalangled portion 64 c (FIG. 9) and the triangular cutout 64 d. Asdiscussed above, triangular cutout 64 d is positioned to receive aprotrusion 65 (FIG. 9B) formed on an inner wall of channel member 22 toretain the distal end of firing assembly 20 within channel member 22.Bottom wall 62 includes a spring arm 66 (FIG. 11) forming a blockingmember which engages a proximal end of slide block 52 to preventproximal movement of slide block 52 beyond a predetermined point withinstationary housing 26.

Guide block 48 includes a body defining three longitudinal slots 70 a-cand a pair of outwardly extending protrusions 72. In one embodiment,each protrusion 72 is substantially cylindrical and includes a taperedportion 72 a (FIG. 9). Alternately, other protrusion configurations areenvisioned. Protrusions 72 are dimensioned to be received in openings 74(FIG. 12) formed in sidewalls 64 of stationary housing 26 to axially fixguide block 48 within the distal end of stationary housing 26.Protrusions 72 allow for a degree of pivotal movement of guide block 48within U-shaped frame 60. As will be discussed in further detail below,guide block 48 is pivotal from a first position (FIG. 19) in lockingengagement with notches 49 and 51 of knife actuating bar 44 to a secondposition (FIG. 26) disengaged from notches 49 and 51 of knife actuatingbar 44 in response to movement of stapler 10 to the clamped position.Each of slots 70 a and 70 c is dimensioned to slidably receive arespective sidewall 114 of cam bar 46. Similarly, slot 70 b isdimensioned to slidably receive knife actuating bar 44.

Slide block 52 (FIG. 12) includes a hub 80 which includes a resilientfinger 80 a configured to be snap-fit into a pivot hole 82 formed infiring lever 50. Firing lever 50 is pivotal about hub 80 when the slideblock 52 is in a retracted position to facilitate actuation of thefiring assembly 20 from either side of stapler 10. Pedal 54 isreciprocally received within a hole 84 formed in slide block 52. Pedal54 includes a split body portion 54 a which is configured to straddle aproximal end 102 of knife actuating bar 44. In one embodiment, splitbody portion 54 a includes an angled distal surface 86. A pin 88 extendsupwardly from pedal 54 through hole 84 in slide block 52. A biasingmember 90 is positioned between split body portion 54 a and slide block52, about pin 88 to urge pedal 54 downwardly away from slide block 52.In the retracted position of slide block 52, pedal 54 is received in acutout 55 formed in a bottom wall 22 a of channel member 22 (FIG. 20).

Firing lever 50 includes first and second finger engagement members 50 aand 50 b, either one of which can be selectively engaged to move thefiring lever 50 through a firing stroke from either side of stapler 10.An arcuate recess 94 (FIG. 12B) is formed in a bottom surface of firinglever 50 which slidably receives pin 88 of pedal 54 to define the rangeof rotation through which firing lever 50 can pivot about hub 80 ofslide block 52. As used herein, a firing stroke is defined as movementof firing lever 50 from a fully retracted position (FIG. 25) to a fullyadvanced position (FIG. 30). A stop recess 94 a is formed at each end ofarcuate recess 94. Stop recesses 94 a are configured and dimensioned toreceive the end of pin 88 of pedal 54 to prevent pivotal movement offiring lever 50 about hub 80 during a firing stroke of surgical stapler10. More specifically, when the firing assembly 20 is actuated toadvance slide block 52 distally within stationary housing 26, angleddistal surface 86 of pedal 54 engages channel member 22 and is cammedout of cutout 55 (FIG. 27) to urge pin 88 upwardly into a stop recess 94a to prevent pivotal movement of firing lever 50 during movement offiring lever 50 through a firing stroke. As is evident, pin 88 must bepositioned beneath a stop recess 94 a to allow pedal 54 to lift upwardlyfrom cutout 55 to allow firing lever 50 to be moved through the firingstroke. Thus, firing lever 50 must be pivoted to one side or the otherof firing assembly 20 before the firing lever 50 can be moved through afiring stroke.

Knife actuating bar 44 includes a proximal end having a stepped portion100 which includes a proximal first step 102 having a first height and asecond step 104 having a second height which is greater than the firstheight. A distal end of actuating bar 44 includes an upturned hookportion 106 and upper and lower notches 49 and 51. A finger 108 projectsupwardly from knife actuating bar 44 between first and second steps 102and 104. As shown in FIG. 27, finger 108 is slidably received within arecess 110 formed in an underside of slide block 52. When slide block 52is advanced distally within stationary housing 26, finger 108 moveswithin recess 110 such that slide block 52 moves in relation to knifeactuating bar 44 until finger 108 engages a wall 112 (FIG. 32) defininga proximal end of recess 110. When finger 108 engages wall 112, furtherdistal movement of slide block 52 will also effect distal movement ofknife actuating bar 44. As will be evident below, this arrangementallows for staples to be ejected from SULU 18 prior to cutting oftissue.

Cam bar 46 includes a pair of sidewalls 114 (FIG. 12) and a base wall116 (FIG. 12A). The proximal end 114 a of each sidewall 114 includes araised wall portion 118. Each raised wall portion 118 is configured tobe fixedly received in a slot (not shown) formed in an underside ofslide block 52 to fixedly secure the proximal end of cam bar 46 to slideblock 52. Alternately, slide block 52 may be molded about the proximalend of knife actuating bar 44. The distal end 114 c of each sidewall 114includes an angled camming surface 114 b. Base wall 116 defines adistally extending elongated slot 123 (FIG. 12A) which extends from thedistal end of cam bar 46 along a substantial length of the cam bar 46and a proximally extending longitudinal slot 121. Slot 121 is positionedto facilitate the passage of pedal 54 through cutout 55 of channelmember 22 when slide block 52 is in the retracted position (see FIG.27).

Sidewalls 114 of cam bar 46 are slidably positioned in slots 70 a and 70c of guide block 48 and knife actuating bar 44 is slidably positioned inlongitudinal slot 70 b of guide block 48. When firing assembly 20 issupported in channel member 22 and firing lever 50 is pivoted to oneside of stationary housing 26 and pushed distally, slide block 52 ismoved distally within stationary housing 26. As slide block 52 begins tomove distally, tapered surface 86 of pedal 54 engages a distal edge ofchannel member 22 defining cutout 55 to urge pedal 54 upwardly out ofcutout 55, through slot 121 of cam bar 46, and onto an inner surface ofstationary housing 26 of firing assembly 20 (FIG. 27). As this occurs,pin 88 of pedal 54 moves into a stop recess 94 a to prevent furtherpivotal movement of firing lever 50. If firing lever 50 is not pivotedto a position in which pin 88 is positioned beneath a stop recess 94 a,pedal 54 will be prevented from moving upwardly out of cutout 55 andfiring lever 50 will be prevented from moving through a firing stroke.As firing lever 50 is moved distally, finger 108 moves within recess 110such that knife actuating bar 44 remains stationary as cam bar 46 isadvanced distally. When finger 108 engages proximal wall 112 definingrecess 110, knife actuating bar 44 is moved distally with slide block 52and cam bar 46. As will be discussed below, when cam bar 46 and knifeactuating bar 44 are moved distally within stationary housing 26 offiring assembly 20 and channel member 22, angled camming surfaces 114 bof cam bar 46 are moved through SULU 18 to eject fasteners from SULU 18.Simultaneously, although with a preset delay equal to the length ofrecess 112 (FIG. 32), knife actuating bar 44 drives a knife blade 40through SULU 18 to dissect tissue.

U.S. Pat. No. 7,631,794 (“the '794 patent”) discloses a surgicalfastener applying apparatus which includes a firing assembly similar tothat described above. The '794 patent is incorporated herein byreference in its entirety.

FIGS. 13-17 illustrate SULU 18. Referring to FIG. 17, SULU 18 includes abody 120, a plurality of staple pushers 122 (only one is shown), abottom cover 124, a knife 40 having an angled sharpened leading edge orblade 40 a, a plurality of staples 126 (only one is shown), and apivotally mounted safety lockout 128. A proximal end of body 120includes a flexible finger 120 a which projects slightly beyond theouter wall defining body 120. Finger 120 a frictionally engages an innerwall of channel member 22 to retain the proximal end of SULU 18 withinchannel member 22 when SULU 18 is releasably positioned within channelmember 22. As is known in the art, body 120 has a plurality of rows ofstaple retaining slots 130, e.g., four, six, etc. and a linear slottedknife track 132 centrally disposed in body 120. Surgical stapler 10 canbe dimensioned to receive or accommodate SULU's of different staple linelengths including, e.g., 60 mm, 80 mm and 100 mm. Knife 40 includes adownturned hook portion 40 b which is positioned to engage upturned hookportion 106 of knife actuating bar 44 when SULU 18 is positioned withinchannel member 22.

In the illustrated embodiment, body 120 includes two staggered rows ofslots 130 formed on either side of linear slotted knife track 132. Thestaggered rows of slots 130 extend beyond the distal end of knife track132 to facilitate staple formation beyond the distal end of the strokeof the knife blade 40.

Staple pushers 122 may be configured to extend into one or more slots130. In one embodiment, a single pusher is associated with each slot130. Alternately, as illustrated in FIG. 17, each pusher 122 can beconfigured to extend into two adjacent slots 130 and is positionedbeneath respective staples 126 which are retained in slots 130. As isknown in the art, each pusher 122 includes a lower cam surface 122 awhich is positioned to engage one of cam surfaces 114 b on the distalend of cam bar 46 such that movement of cam bar 46 through SULU 18sequentially lifts each respective pusher 122 within its respective slotor slots 130 to eject staples from slots 130.

Bottom cover 124 partially encloses a channel 125 (FIG. 18) formedwithin the cartridge body 120. A longitudinal ridge 134 is formed on anupper surface of bottom cover 124 and provides a bearing surface for aknife supporting member 136 which is secured to a bottom edge of knife40. Knife 40 may be secured to supporting member 136 via pins, weldingor other known fastening techniques. During a firing stroke, knife 40 isguided along knife track 132 as the firing lever 50 is advanced throughchannel member 22. A pair of slots 138 are defined between the sides ofridge 134 and an outer wall of cartridge body 120. Longitudinal ridge134 is positioned within body 120 and dimensioned to be slidablyreceived in elongated slot 120 (FIG. 12a ) of cam bar 46 such that cambar 46 is slidably movable through cartridge body 120 about longitudinalridge 134 to eject staples 126 from SULU 18.

Safety lockout 128 is pivotally disposed on an upper proximal end ofbody 120 and is pivotal about a pivot member 150 (FIG. 17) from a lockedorientation (FIG. 26) to unlocked orientation (FIG. 34). Pivot member150 is received in openings 154 in body 120. A biasing member, e.g.,spring 152, is positioned between knife supporting member 136 and safetylockout 128 to urge safety lockout 128 towards the unlocked orientation.Safety lockout 128 includes a proximal hook 156 which is positioned toreceive an engagement member 158 formed on the knife 40 to retain thesafety lockout 128 in the locked orientation when the knife 40 is in theretracted position (FIG. 19). When the knife 40 is moved towards theadvanced position during a firing stroke, engagement member 158 is movedaway from proximal hook 156 to allow safety lockout 128 to pivot towardsthe unlocked position in response to the urging of spring 152. It isnoted that safety lockout 128 is prevented from pivoting to the unlockedposition when the anvil half-section 12 and cartridge receivinghalf-section 14 are in the clamped position because the top surface 128a of safety lockout 128 engages an inner surface of anvil half-section12 to prevent pivoting of safety lockout 128. Safety lockout 128 definesa slot 160 dimensioned to slidably receive the knife 40. In theretracted position of the knife 40, the leading edge 40 a of knife 40 isconfined within slot 160 safety lockout 128 to prevent accidentalengagement and injury to medical personnel with leading edge 40 a ofknife 40.

Referring again to FIGS. 2-3, anvil half-section 12 includes a proximalhandle portion 12 a and a distal anvil portion 12 b. Anvil portion 12 bincludes a staple deforming portion 198 which, as known in the art,includes a plurality of staple deforming recesses and faces a topsurface of SULU 18 when SULU 18 is positioned in the channel member 22.As is also known in the art, the staple deforming portion 198 includes acentral longitudinal slot (not shown) for receiving the knife 40 as theknife 40 is moved through the SULU 18. The staple deforming portion 198can be formed integrally with anvil half-section 12, or in thealternative, secured to anvil half-section 12 by a fastening processsuch as welding. A pair of locating fingers 170 are positioned adjacentthe proximal end of the staple deforming portion 198 of anvil portion 12b and function to properly align SULU 18 with staple deforming portion198.

A central portion of anvil half-section 12 includes a pair ofcylindrical lateral support members 172. During assembly of anvilhalf-section 12 and cartridge receiving half-section 14, lateral supportmembers 172 are supported in U-shaped recesses 174 formed on a centralportion 173 of cartridge receiving half-section 14 (FIG. 28). Lateralsupport members 172 are also positioned to be received in cutouts 176formed on spaced flange portions 178 of clamping lever 16 when theclamping lever 16 is moved toward the clamped position (see FIGS. 1 and2B). Proximal handle portion 12 a is ergonomically formed and includes athumb-engaging abutment 180 and a gripping portion 182. A proximal endof handle portion 12 a includes a downwardly extending finger 184 whichincludes a pair of opposed teardrop shaped protrusions 186 which will bediscussed in further detail below. Protrusions 186 may assume a varietyof configurations.

Cartridge receiving half-section 14 includes a central portion 173 whichdefines spaced centrally disposed U-shaped recesses 174 positioned tosupport lateral support members 172 of anvil half-section 12. A distalwall 173 a of central portion 173 defines a tissue stop. A pair oflateral cylindrical pivot members 187 are positioned beneath recesses174. Each pivot member defines a flat 187 a (FIG. 2a ).

The proximal end of cartridge receiving half-section 14 also includes apair of vertical support members 188. Each vertical support member 188includes an elongated vertical slot 188 a having a rounded bottomsurface. Vertical slots 188 a are dimensioned to receive protrusions 186formed on finger 184 of anvil half-section 12 (see also FIG. 21) whenthe anvil half-section 12 is supported on the cartridge receivinghalf-section 14 during assembly. By positioning protrusions 186 withinvertical slots 188 a, anvil half-section 12 can be pivoted in ascissor-like action with respect to the cartridge receiving half-section14 between open and closed positions. In one embodiment, protrusions 186have a tear drop profile. At least one sidewall of cartridge receivinghalf-section 14 includes a depression 189 (see FIG. 3) which will bediscussed in further detail below.

Clamping lever 16 also includes a handle portion 190 including a grip190 a and a thumb engaging abutment 192. As discussed above, a pair ofspaced flange portions 178 are supported on the distal end of clampinglever 16. Each flange portion 178 defines a cutout 176 dimensioned toreceive a respective lateral support member 172 of anvil half-section 12when stapler 10 is moved towards the clamped position (FIG. 2B). Thedistal end of clamping lever 16 also defines a pair of distal C-shapedrecesses 194 which are dimensioned to receive pivot members 187. Eachrecess 194 defines a mouth which is smaller in width than the diameterof the pivot members 187 of cartridge half-section 14. Because the mouthof each C-shaped recess 194 is smaller in width than the diameter of thepivot member 187, when clamp lever 16 is secured to cartridge receivinghalf-section 14 (FIG. 24), the pivot members 187 must be slid intorecesses 194 along the surface of flats 187 a of the pivot members 187.As such, clamping lever 16 must be positioned as shown in FIG. 2A topivotally secure clamping lever 16 about pivot members 187 of cartridgereceiving half-section 14. After positioning pivot members 187 inC-shaped recesses 194, clamping lever 16 can be rotated in acounter-clockwise direction as shown in FIG. 2A to the position shown inFIG. 2 to secure clamp lever 16 to cartridge receiving half-section 14.As can be appreciated, to attach clamping lever 16 to pivot member 187,clamping lever 16 is positioned at an obtuse angle with respect to thecartridge receiving half-section proximal portion as shown in FIG. 2A.Clamping lever 16 is then pivoted to an attached but unclamped positionat an acute angle with respect to the proximal portion of the cartridgereceiving half-section 14 as shown in FIG. 18.

As shown in FIG. 3A, an inner wall of clamping lever 16 includes aprotrusion 201. As clamping lever 16 is rotated from the position shownin FIG. 2A to the position shown in FIG. 2B, protrusion 201 moves alongand is deformed by an outer wall of cartridge receiving half-section 14until protrusion 201 moves into depression 189 (FIG. 2A) formed in thesidewall of cartridge receiving half-section 14. By positioningprotrusion 201 in depression 189, clamping lever 16 is prevented fromrotating to a position in which the clamping lever 16 can be disengagedfrom the cartridge receiving half-section 14 (FIG. 2A) unless asufficient force is applied in the opposing direction.

Referring to FIG. 2, after clamping lever 16 has been secured tocartridge receiving half-section 14 and SULU 18 and firing assembly 20are loaded into channel member 22, anvil section 12 can be assembled tocartridge receiving half-section 14. It is noted that SULU 18 and firingassembly 20 can be loaded into channel member 22 prior to or aftersecurement of clamping lever 16 to cartridge receiving half-section 14.To attach anvil half-section 12 to cartridge receiving half-section 14,protrusions 186 of finger 184 are positioned in vertical slots 188 a ofvertical support member 188 of cartridge receiving half-section 14.Thereafter, anvil half-section 12 is rotated towards cartridge receivinghalf-section 14 to position lateral support members 172 in U-shapedrecesses 174.

In order to position surgical stapler 10 in the clamped position,clamping lever 16 is rotated in a counter-clockwise direction from theposition shown in FIG. 2B. As clamping lever 16 is rotated, lateralsupport members 172 are received in cutouts 176 of flange portions 178of clamping lever 16 and cammed towards cartridge receiving half-section14. As shown in FIG. 3, a spring member 200 is secured to an innersurface of clamping lever 16, such as by welding, at a position toengage cartridge receiving portion 14 to urge clamping lever 16 to thenon-clamped position of FIG. 2B. In the clamped position shown in FIG.1, the staple deforming portion 198 of anvil half-section 12 ispositioned in close approximation with the top surface of SULU 18.

Referring to FIGS. 18 and 22-27, the proximal end of clamping lever 16includes a cutout 204, a resilient cantilevered locking member 206positioned within the cutout 204, and a resilient engagement member 208supported on the locking member 206. Locking member 206 defines anopening 210 and a finger engagement surface 212. Engagement member 208defines a hook portion which is positioned within opening 210 andincludes a transverse locking surface 208 a. In one embodiment, thecantilevered locking member 206 is integrally formed with clamping lever16 and is connected to clamping lever 16 by a living hinge 213 (FIG.23). Referring to FIGS. 3, 25 and 27, the proximal end of cartridgereceiving half-section 14 includes a catch member 214 which extendsdownwardly from cartridge receiving half-section 14. In one embodiment,catch member 214 is integrally formed with half-section 14 and has atransverse locking surface 214 a. Catch member 214 is positioned to bereceived within opening 210 and to engage and deflect engagement member208 inwardly when clamping lever 16 is moved to the clamped positionsuch that locking surface 208 a of engagement member 208 automaticallysnaps into releasable engagement with locking surface 214 a when clamplever 16 is moved to the clamped position to retain clamping lever 16 inthe clamped position. To accomplish this, locking member 214 andengagement member 208 define angled cam surfaces which abut duringmovement of the clamping lever 16 to the clamped position to deflectengagement member 208 inwardly past catch member 214. In order torelease engagement member 208 from catch member 214, cantileveredlocking member 206 can be depressed by pressing on finger engagementsurface 212 to move engagement member 208 inwardly out of engagementwith catch member 214. When this occurs, spring member 200 automaticallyurges clamping lever 16 to the unclamped position.

Referring to FIGS. 3, 12, 19 and 26, as discussed above, guide block 48is pivotally supported in stationary housing 26 of firing assembly 20.Guide block 48 includes a distally extending nose portion 220 (FIGS. 12and 26) which rests beneath SULU 18 when SULU 18 is supported in channelmember 22. The internal surface of guide block 48 includes lockingsurfaces 222 (FIG. 19) which are received in notches 49 and 51 of knifeactuating bar 44 when the stapler 10 is in an unclamped position. Whenthe SULU 18 is positioned in the channel member 22, prior to movingclamp lever 16 to the clamped position, SULU 18 is positioned atop noseportion 220 and is not fully seated in the channel member 22, asdiscussed above. When the stapler 10 is moved to the clamped position,locating fingers 170 of anvil half-section 12 (FIG. 3) engage a topsurface of body 120 of SULU 18 to fully seat SULU 18 in channel member22. Locating fingers 170 engage SULU 18 to properly position SULU 18 inrelation to anvil portion 12 b. As SULU 18 is fully seated in channelmember 22, SULU 18 presses downwardly on nose portion 220 of guide block48 to pivot guide block 48 about protrusions 72. When guide block 48pivots, locking surfaces 222 move from notches 49 and 51 to unlock knifeactuating bar 44 (FIG. 26). This configuration prevents movement of theknife actuating bar 44 in relation to guide block 48 prior to clampingto ensure that the knife actuating bar 44 and SULU knife 40 remainproperly positioned for operational engagement prior to use.

Referring to FIGS. 24-28, when stapler 10 is in the clamped, unfiredposition, slide block 52 of firing assembly 20 is in the retractedposition at the proximal end of channel member 22 and stationary housing26 (see FIG. 27). In this position, pedal 54 is positioned in cutout 55of channel member 22 and pin 88 of pedal 54 is positioned in arcuaterecess 94 of firing lever 50 beneath stop recesses 94 a. As such, firinglever 50 can be pivoted to facilitate actuation of stapler 10 fromeither side of the stapler 10. In addition, in this position of slideblock 52, finger 108 of knife actuating bar 44 is positioned adjacentthe distal wall of recess 110 of slide block 52. Engagement member 208is also engaged with locking member 214 to retain clamping lever 16 inthe clamped position.

When slide block 52 is in the retracted position, knife 40 and camsurfaces 114 b of cam bar 46 are positioned in the proximal end of SULU18 and, proximal hook 156 of safety lockout 128 is positioned inengagement with engagement member 158 of knife 40 to retain safetylockout 128 in the locked orientation. In addition, downturned hookportion 40 b of knife 40 is engaged with upturned hook portion 106 ofknife actuating bar 44 to connect firing assembly 20 to knife 40 of SULU18.

When the firing lever 50 is advanced distally in the direction indicatedby arrow “A” in FIG. 29, slide block 52 is moved distally withinstationary housing 26 of firing assembly 20 to effect correspondingmovement of cam bar 46 and delayed movement of knife actuating bar 44(see FIGS. 30-32). As discussed above, the delayed movement of the knifeactuating bar 44 is equal to the length of recess 110 of slide block 52and results from movement of finger 108 of knife actuating bar 44 withinrecess 110 of slide block 52. Movement of knife actuating bar 44 withslide block 52 begins when finger 108 abuts the proximal wall 112 ofrecess 110. As cam bar 46 is moved distally through stationary housing26 of firing assembly 20, cam surfaces 114 b on sidewalls 114 of cam bar46 are advanced through SULU 18 to sequentially engage pushers 122 toeject staples 126 from slots 130 of body 120. Concurrently, since thedistal end of knife actuating bar 44 is engaged with knife 40, knife 40,after the preset delay, is advanced through SULU 18 to incise tissuebetween the staple lines.

As shown in phantom in FIG. 32, when slide block 52 moves distallywithin stationary housing 26, pedal 54 rides up over channel member 22and moves along inner surface of stationary housing 26 of firingassembly 20. When this occurs, pin 88 of pedal 54 moves into a stoprecess 94 a to prevent further pivotal movement of firing lever 50.

When knife 40 is moved distally within SULU 18, engagement member 158 ofknife 40 is disengaged with proximal hook 156 of safety lockout 128.

When the firing lever 50 is returned to its proximal-most position toretract cam bar 46 and knife 40, as shown in FIGS. 33 and 34, and thecantilevered locking member 206 is depressed to disengage engagementmember 208 from catch member 214, spring 200 urges clamping lever 16 toits unclamped position to allow stapler 10 to move to the open position.In the open position, anvil half-section 12 is spaced from cartridgereceiving half-section 14 and spring 152 (FIG. 17) pivots safety lockout128 in the direction indicated by arrow B in FIG. 34 about pivot member150 to its unlocked position such that safety lockout 128 projectsupwardly from SULU 18. In the unlocked position, safety lockout 128prevents movement of the stapler 10 back to the clamped position. Inorder to reuse stapler 10, used SULU 18 must be replaced with a new SULU18.

During a surgical procedure, SULU 18 can be replaced multiple times tofacilitate multiple uses of stapler 10 on a single patient. If anintegrated unit is provided, the SULU and firing assembly can bereplaced multiple times. Since each SULU 18 is provided with a freshknife 40, tearing of tissue is minimized. After the surgical procedure,the used SULU(S) 18 and the firing assembly 20 can be removed from thechannel member 22 and disposed of in an appropriate manner. Thereafter,clamping lever 16 can be removed from cartridge receiving half-section14 by rotating clamping lever 16 (forcing protrusion 201 out of and pastdepression 189) to the position shown in FIG. 2A (aligned with flats 187a of pivot members 187) and disengaging pivot members 187 from C-shapedrecesses 194. The anvil half-section 12, cartridge receivinghalf-section 14 and clamping lever 16, as separated units, can now besterilized, such as by autoclaving, and reused with a new SULU 18 andfiring assembly 20 in the manner discussed above.

It will be understood that various modifications may be made to theembodiments of the surgical fastener applying apparatus disclosedherein. Therefore, the above description should not be construed aslimiting, but merely as exemplifications of embodiments. Those skilledin the art will envision other modifications within the scope and spiritof the present disclosure.

What is claimed is:
 1. A surgical fastener applying apparatuscomprising: an anvil half-section including a distal anvil portion and aproximal handle portion; a cartridge receiving half-section defining anelongated channel member, the elongated channel member having a distalportion dimensioned to releasably receive a cartridge and a proximalportion configured to support a firing assembly, the elongated channelmember including a catch member positioned at the proximal portion; anda clamping lever secured to the cartridge receiving half-section, theclamping lever having a proximal portion and a distal portion andincluding a handle portion, the clamping lever including a cantileveredlocking member integrally formed with the proximal portion of theclamping lever and including a living hinge, the cantilevered lockingmember including an engagement member; the clamping lever being operablyassociated with the anvil half-section and the cartridge receivinghalf-section and being movable from an unclamped position to a clampedposition to releasably secure the anvil portion of the anvilhalf-section in close approximation with the cartridge, wherein in theclamped position, the engagement member of the cantilevered lockingmember releasably engages the catch member of the elongated channelmember to releasably retain the clamping lever in the clamped position.2. The surgical fastener applying apparatus according to claim 1,wherein the cantilevered locking member includes a finger engagementsurface, the finger engagement surface being depressible to effectdisengagement of the engagement member and the catch member.
 3. Thesurgical fastener applying apparatus according to claim 2, wherein thefinger engagement surface is proximal of the engagement member.
 4. Thesurgical fastener applying apparatus according to claim 1, wherein aproximal most end of the clamping lever defines a cutout, thecantilevered locking member being supported within the cutout.
 5. Thesurgical fastener applying apparatus according to claim 4, wherein thecantilevered locking member includes an opening, the engagement memberbeing positioned within the opening.
 6. The surgical fastener applyingapparatus according to claim 5, wherein the engagement member defines ahook portion having a transverse locking surface.
 7. The surgicalfastener applying apparatus according to claim 1, further comprising aspring member which is supported on the clamping lever and positioned toengage the cartridge receiving half-section to urge the clamping leverto the unclamped position.
 8. The surgical fastener applying apparatusaccording to claim 1, further including a firing assembly, the firingassembly being configured to be releasably secured within the proximalportion of the cartridge receiving half-section and including a firinglever and a cam bar fixedly secured to the firing lever.
 9. The surgicalfastener applying apparatus according to claim 8, wherein the firingassembly includes a stationary housing, the stationary housing having asidewall with a slotted proximal end to define a cantilevered sectionwith a protrusion, the cantilevered section flexible inwardly toreleasably secure the firing assembly within the cartridge receivinghalf-section.
 10. The surgical fastener applying apparatus according toclaim 8, wherein the firing assembly includes a stationary housing, thestationary housing including a blocking member to prevent proximalmovement of a slide block of the firing assembly.
 11. The surgicalfastener applying apparatus according to claim 1, wherein the cartridgereceiving half-section includes a sidewall defining a depression and theclamping lever includes a sidewall defining a protrusion, the protrusionbeing positionable within the depression to prevent the clamping leverfrom moving to a position where it could be disengaged from thecartridge receiving section.
 12. The surgical fastener applyingapparatus according to claim 1, wherein the clamping lever is releasablysecured to the cartridge receiving half-section.
 13. A surgical fastenerapplying apparatus comprising: an anvil half-section including a distalanvil portion and a proximal handle portion; a cartridge receivinghalf-section defining an elongated channel member, the elongated channelmember having a distal portion dimensioned to releasably receive acartridge and a proximal portion configured to support a firingassembly, the elongated channel member including a stationary catchmember positioned at the proximal portion of the elongated channelmember; and a clamping lever pivotally supported on the cartridgereceiving half-section, the clamping lever including a handle portion, acantilevered locking member integrally formed with the handle portionand including a living hinge interconnecting the proximal portion of thehandle portion with the cantilevered locking member, the cantileveredlocking member including an engagement member; wherein the clampinglever is operably associated with the anvil half-section and thecartridge receiving half-section and is movable from an unclampedposition to a clamped position to releasably secure the anvil portion ofthe anvil half-section in close approximation with the cartridge, theengagement member of the cantilevered locking member being releasablyengaged with the catch member of the elongated channel member in theclamped position to releasably retain the clamping lever in the clampedposition.
 14. The surgical fastener applying apparatus of claim 13,wherein the cantilevered locking member defines an opening and theengagement member is positioned within the opening.
 15. The surgicalfastener applying apparatus of claim 14, wherein the engagement memberis resilient and defines a hook portion.
 16. The surgical fastenerapplying apparatus of claim 15, wherein the catch member is configuredto be received within the opening of the cantilevered locking member andincludes a locking surface.
 17. The surgical fastener applying apparatusof claim 16, wherein the catch member is positioned to engage anddeflect the engagement member to move the engagement member intoreleasable engagement with the locking surface of the catch member.